Generally, a circuit breaker disposed on a distribution board of semiconductor or LCD equipment is a device having a function of cutting off, when fault current such as leakage current or overcurrent occurs on a line, the supply of the fault current to the distribution board. The circuit breaker has a padlock (external manipulating handle) operating cooperatively with a door of the distribution board to cut off electric power when the door is open and to supply electric power when the door is closed.
As shown in FIG. 1, a conventional padlock, which is disclosed in Korean Patent Registration No. 10-2004-0107303 (entitled ‘external manipulating handle device of circuit breaker for distribution’), includes: a handle case 50 serving as a support for internal components thereof upon the operations of the internal components and having a handle fastenedly assembled to a circuit breaker for distribution; a manipulating handle 20 attached to top of the handle case 50 to allow the handle to be manipulated to the outside by means of the rotation thereof; a pinion gear 80 connected to the manipulating handle 20 to transmit the rotary force of the manipulating handle 20; a rack gear 90 engaged with the pinion gear 80 to transfer a rotary motion to a linear motion and thus to manipulate the handle; and guide rails 100 fixed to the handle case 50 to guide the operation of the rack gear 90.
According to the external manipulating handle device of the circuit breaker for distribution, the manipulating handle 20 mounted on the door of the distribution board is operated so that the pinion gear 80, the rack gear 90, the guide rails 100, and the handle 70 are cooperatively operated with each other, thereby turning on/off the circuit breaker for distribution. That is, the conventional external manipulating handle device is disposed separately from a circuit breaker for the distribution board and is manually manipulated to the outside of the distribution board.
In addition, the circuit breaker for the distribution board is disposed near to the door by means of the manipulating handle 20, thereby making it difficult to ensure the space of the distribution board itself, and a separate device for the manual manipulation of the manipulating handle 20 is needed, thereby making the whole configuration complicated and lowering the reliability of the external manipulating handle device.
Further, as shown in FIG. 2, there is proposed a motor interlock device of a circuit breaker for distribution, which is disclosed in Korean Utility Model Registration No. 20-2005-0030166, including: a motor 302 for generating a rotary motion; an axle 304 connected to the motor 302 in such a manner as to move forward and backward in left and right directions according to the rotary directions of the motor 302; and an operator 306 adapted to apply a force to one of two handles 310 of the circuit breaker for distribution in a direction of power supply and to apply a force to the other handle in a direction of power cut-off according to the left and right motions of the axle 304.
According to the conventional motor interlock device of the circuit breaker for distribution, the inconveniences caused by the manual manipulation of the circuit breaker are removed, but the motor 302 operating by an external control signal, the axle 304 driven by the motor 302, and the operator 306 manipulating the handles 310 through the driving of the axle 304 should be disposed separately from the circuit breaker for distribution. Further, the circuit breaker for the distribution board is disposed near to the door, thereby making it difficult to ensure the space of the distribution board itself.